This blog post is different from all other posts I’ve already published. I swapped my keyboard for a soldering iron and IDE for a circuit board to build a DIY hi-fi stereo system.

Parts list

  • High quality 2-way bookshelf loudspeakers
  • Multimedia streaming box
  • Class D digital power amplifier board
  • Optical DAC (Digital Analog Converter) board
  • Step down power supply board
  • 3D printed housing

Bookshelf speakers

My requirements:

  • Bookshelf speakers with modern and minimalist design
  • Decent sound quality
  • Sized to my living room – 35 m²
  • Budget $300

Trusted expert recommended JBL Stage A130, 2 way, 5.25” woofer, 1” aluminum tweeter bookshelf loudspeakers. I visited local home audio store, listen for a while to get my own opinion and … put the box with the speakers to the car - they sound amazing 😀

JBL Stage A130

Multimedia streaming box

My requirements:

  • Optical S/PDIF output
  • Integration with Spotify Connect and other streaming platforms
  • Easy to use for my family members
  • Power efficient
  • Budget $50

I found a used TV box with Android 11 based on the powerful Amlogic S905X4 SoC.

TV box

Class D digital power amplifier board

My requirements:

  • Based on opinionated Class-D audio amplifier chip
  • With enough power to drive JBL Stage A130 speakers
  • Well made using high quality capacitors and coils

I decided for amplifier board based on TPA3255 chip from Aliexpress, model BDM8-A.

Amplifier board

Optical DAC decoder board

My requirements:

  • Based on opinionated DAC chip
  • Optical S/PDIF input

I decided for DAC board based on CS8416 and CS4398 chips from Aliexpress with up to 24bits at 192kHz sampling.

Digital analog converter board

Step down power supply board

My requirements:

  • With enough power to drive TPA3255 amplifier and 6Ω speakers
  • Power efficient
  • With low noise ripple
  • Small and light

Some math to estimate maximum power available with 24V DC power supply and 6Ω speakers:

  1. 24V DC => 24V / √2 ~= 17V AC
  2. 17V^2 / 6Ω = 48W

48W per channel looks fine for selected speakers and size of my living room, lets calculate current consumption:

  1. 17V / 6Ω = 2.83A
  2. 2.83A * 2 (channels) = 5.66A

I decided for power supply board from Aliexpress, version: 24V/6A.

Power supply board

Other parts

  • Transformer 2×12V 0.08A for DAC
  • Universal circuit board
  • Power socket
  • Circuit breakers
  • Connectors and cables
  • Nylon screws, nuts and spacers
  • PLA filament for 3D print


Component layout to get low profile housing and all connectors on the back side:

Amplifier - layout

Working prototype in the cardboard box:

Amplifier - prototype

Assembly on a thin furniture board:

Amplifier - plate


My 3D printer has a maximum print volume of 18×18×18 cm, so I printed the housing in two parts.

Left side 3D model:

3D - left

Right side 3D model:

3D - right

After just 14 hours of printing, I could make the first adjustments:

Amplifier - case

Final result

Amplifier - final

If I had to sum up why it’s worth playing DIY:

  1. Educational Aspect: Constructing a multimedia stereo system from parts is an excellent way to learn about electronics, audio system design, Android TV and 3D printing.

  2. Satisfaction: There’s a sense of accomplishment in creating something functional and beautiful. I was most proud that the first 3D printed housing fit like a glove.

  3. Customization: When you build your own amplifier, you have complete control over the design. You can tailor it to your preferences, for example I didn’t want any hardware knobs.

  4. Cost Savings: DIY amplifiers can be more affordable than commercial high-end options but you can’t count your time.

I would also like to thank Jacek for his inspiration and help.